Manufacturing of decorative workpieces by inkjet

ABSTRACT

A method for manufacturing decorative workpieces includes the step of nesting a set of decorative patterns digitally printed on a decoration layer to reduce the waste of decoration layer. To perform a corresponding relief for the nested decorative patterns on a nested decorative workpiece, the relief provided by a digital relief apparatus is in a correct match with the nested decorative workpiece. If the printing zone of the digital printer has a failure zone, the nesting method prevents arranging of the decorative patterns in this failure zone.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a 371 National Stage Application ofPCT/EP2015/052165, filed Feb. 3, 2015. This application claims thebenefit of European Application No. 14154309.0, filed Feb. 7, 2014,which is incorporated by reference herein in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to methods for manufacturing decorativeworkpieces such as decorative panels.

2. Description of the Related Art

Gravure, offset and flexography are being increasingly replaced fordifferent applications by industrial inkjet printing systems, which havenow proven their flexibility in use, such as variable data printingmaking short production runs and personalized products possible, andtheir enhanced reliability, allowing incorporation into productionlines.

Inkjet technology, as digital printing technology has also caught theattention of manufacturers of decorative surfaces, such as laminatefloor. In the current production process for manufacturing decorativepanels as shown by FIG. 1, a paper manufacturer (11) supplies a paperroll (12) to a decor printer (13) who uses gravure printing (14) inorder to deliver a decor paper roll (16) to a warehouse (17) of a floorlaminate manufacturer (20). Some decor printers (13) are nowinvestigating inkjet printing (15) instead of gravure printing.Rotogravure printing on the porous decor paper generally uses ink havinga viscosity at 25° C. of 1 to 2 Pa·s, while the viscosity of inkjet inksis much lower, often about 1 to 15 mPa·s at 25° C. The floor laminatemanufacturer (20) stores the decor paper rolls (16) having differentdecorative patterns in his warehouse (17). Depending on the marketdemand, the floor laminate manufacturer (20) then selects the decorrolls (16) with the desired decorative pattern in his warehouse (17).The selected decor rolls (16) are then impregnated (18) and cut to size(19) for manufacturing ready-to-use floor laminate (21). The warehouse(17) is necessary as a buffer for sudden large market demands of aspecific floor laminate because there is a large time delay betweenordering and delivering of new decorative paper rolls (16).

An approach to reduce the size of the warehouse and time delays istreated by EP 2431190 A (THEODOR HYMMEN), which discloses in FIG. 1 amethod for producing a digitally printed sheet, web or plate-shapedworkpiece (20) with wear-resistant surface including the steps of: A)providing a digital data set to a digital printing device (1); B)providing a printable workpiece (20) to the printing apparatus (1); C)digital printing at least an acrylate printing ink (22) on the printableworkpiece (20) using the printing apparatus (1) and thereafter supplyinga resin mixture (5, 21) to the digitally printed workpiece; and D)curing the resin mixture (5, 21) by means of a heated press (7). Thetime delay can be avoided by the floor laminate manufacturerincorporating the manufacturing of decorative paper rolls into its ownproduction process.

Also aqueous inkjet inks have been used for manufacturing decorativelaminates by single pass inkjet printing. For example, in the Palisroll-to-roll single pass printing systems(http://www.palis-digital.com/en/portfolio/sp-drucker.html) aqueousinkjet inks are printed on a paper substrate having a special inkacceptance layer.

An increase in waste of decorative workpieces has been observed onperforming the digital printing of decorative patterns at the facilitiesof the laminate manufacturer. This increase of waste is observed notonly in the more frequent short run productions, but especially whensizes of digital printed decorative patterns are different or when theshapes of digital printed decorative patterns are different. Therefore,there is a need to reduce the waste of decoration layer and workpieces.

DE102006057961 (BAUER JOERG) discloses a method of producing floorpanels wherein an arrangement method is disclosed in FIG. 1 anddescribed in [0027] but is silent about details in this arrangementmethod and the reasons behind this kind of arrangement.

EP2695746 (UNILIN BVBA), which became public available on 12 Feb. 2014,with a date of filing on 6 Aug. 2012, discloses a method whereinmultiple rectangular-shaped decorative patterns are printed on adecoration layer but wherein the decorative patterns are arranged inpredetermined areas based on the dimension of the predetermined areas.Therefore the dimensions of the decorative patterns are also fixed. Butthey are not a solution wherein multiple decorative patterns have to bearranged on a decoration layer and wherein the dimensions and shapes ofthe decorative patterns have a lot of variances.

DE102010036454 (FRITZ EGGER GMBH) discloses a similar method forarrangement of decorative patterns as in EP295746 (UNILIN BVBA) but alsoin here the decorative patterns are arranged in predetermined areasbased on the dimension of the predetermined areas. Therefore thedimensions of the decorative patterns are also fixed. But they are not asolution wherein multiple decorative patterns have to be arranged on adecoration layer and wherein the dimensions and shapes of the decorativepatterns have a lot of variances.

SUMMARY OF THE INVENTION

Preferred embodiments of the present invention have been realised with amethod for manufacturing decorative surfaces as defined below.

The present invention reduces the waste of decoration layers whereon aset of decorative patterns are digital printed and to reduce the wasteat the finishing (for example cutting) of the decorative workpieces,especially when the dimensions of the set of decorative patterns aredifferent or when the shapes of the set of decorative patterns aredifferent, an arbitrary way of arranging on the decoration layer causemore waste of decoration layer. The reduction of the waste is obtainedby a nesting method. The nesting method arranges a set of decorativepatterns as such that the amount of “decoration layer”-waste is muchsmaller than arranging the set of decorative patterns in an arbitraryway. The nesting method reduces also the environmental impact byreducing the waste of decoration layer in the manufacturing ofdecorative workpieces. In a nesting method it is obvious that the amountof decorative patterns in the set of decorative patterns is two or more.A nesting method takes the shape of the decoration patterns and the sizeof the decoration layer into account to maximize the number ofdecorative patterns that can be arranged on a decoration layer so nopredetermined and fixed areas are needed to arrange them. The nestingmethod guarantees a minimum waste.

In a preferred embodiment the nested decorative patterns are printed byan inkjet print device and in a more preferred embodiment the nesteddecorative patterns are printed by a single pass inkjet print device.

Preferably the nesting method is a rectangular nesting method. Therectangular nesting method is preferred if the decorative patterns arerectangular shaped. To reduce the waste of decoration layer even morethe nesting method is a true shape nesting method wherein the shape ofthe decorative patterns is taken into account when arranging thedecorative patterns on the decoration layer.

The nesting method preferably arranges also the relief content of thedecorative patterns so the nested relief contents matches accordinglywith the nested decorative patterns when providing the nested reliefcontents to the nested decorative workpiece.

An advantage of a nesting method is the ability to quickly respond onspecific situations during the manufacturing of decorative workpieces.For example, the current technology of digital print devices hasfundamental weaknesses compared to conventional print devices such asrotogravure or offset, especially when it comes to high-speed digitalprinting of decorative patterns on a decoration layer. When a digitalprint device fails to print in a specific zone at the moment themanufacturing of the decorative workpieces have to be stopped to solvethe failing of the digital print device, this has an impact on theproduction and manufacturing timings. The nesting method may arrange theset of decorative patterns digital printed on the decoration layer inthe quality zone of a digital print device and/or in the quality zone ofa cutting plotter so that the manufacturing can continue fast withoutthe need of directly solving the failing. A specific failing of adigital print device is the malfunction of a nozzle in an inkjet printhead of an inkjet print device. In a single pass inkjet print devicethis causes a non-printed line in the print zone of the single passinkjet print. By preventing not to nest a decorative pattern in thenon-printed line the manufacturing of the decorative workpiece cancontinue without maintenance the failing nozzle of the inkjet printhead.

Another way to prevent digital printing of a decorative pattern in afailure zone of a single pass inkjet printer, is to reduce the printzone of the single pass inkjet print in the direction across thetransport direction of the decorative layer so the quality zone has thesame dimension as the print zone of the single pass inkjet printer.

Digital printing of decorative patterns for the manufacturing decorativeworkpieces gives the ability to react fast on the demands of thedecorative workpiece market by printing on demand. The nesting method inthe preferred embodiment may be prepared to react even faster byarranging decorative patterns on the decoration layer while digitalprinting already arranged decorative patterns on the decoration layer.In a preferred embodiment the nesting method is a nesting-on-the-flymethod. Preferably in this nesting-on-the-fly method the nesteddecorative patterns are printed by a single pass inkjet printer.

It was noticed that high ink coverage or toner coverage in a decorativepattern may cause delaminating of the decoration workpiece or otherquality issues. In a preferred embodiment a decorative pattern isselected from a decorative image as region-of-interest wherein thecontent of the region-of-interest is analysed by an image analysismethod. The image analysis method may prevent that decorative patternshall be nested because it is controlled that it gives quality issues inthe manufacturing of decorative workpieces. The nesting method mayselect a region-of-interest in the decorative image which may asdecorative pattern nested without quality issues such as delaminating ofthe decoration workpiece.

The selection may be based on the image analysis of

-   -   counting the amount of knots; and/or    -   measuring the size of knots; and/or    -   measuring the distance of a knot and the edge of a        region-of-interest in the decorative image; and/or    -   measuring the density of wood grain lines.

The finishing, such as cutting, of a nested decorative workpiece maycause some inaccuracies therefore in a preferred embodiment a bleed areais added to a decorative pattern to compensate the inaccuracies of thefinishing of the workpiece. A connect area to the decorative pattern mayalso be added wherein means shall be provided to attach decorativeworkpieces together such as a tongue-and-groove profile.

The nesting method is preferably contained in a deco digital workflowsystem to reduce the total waste of the manufacturing decorativeworkpieces. Preferably the deco digital workflow system comprises amanagement information system (MIS).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a nesting method (100) of six decorative patterns(201, 202, 203, 204, 205, 206) on a flexible web (301), as decorationlayer, whereon the nested decorative patterns (201, 202, 203, 204, 205,206) are printed. Only a part of the flexible web material (301) isshown. The nesting method (100) nested one decorative pattern (206) withthree copies. The waste of decoration layer is minimized in the nestingmethod by, for example ninety degrees rotating of decorative patterns(201, 202, 203, 204). The six decorative patterns (201, 202, 203, 204,205, 206) are added in a nesting queue (150).

FIG. 2 illustrates a nesting method (100) of four decorative patterns(201, 202, 205, 207) on a flexible sheet (302), as decoration layer,whereon the nested decorative patterns (201, 202, 205, 207) are printed.The nesting method (100) nested a decorative pattern (201) in threecopies, a decorative pattern (202) in four copies, a decorative (205) inthree copies and decorative pattern (207) in one copy. The fourdecorative patterns (201, 202, 205, 207) are added in a nesting queue(150). The nesting method arranged the copies of the decorative patterns(201, 202, 205, 207) to minimize the waste of decoration layer. The fourdecorative patterns (201, 202, 203, 205, 207) are added in a nestingqueue (150).

FIG. 3 illustrates a nesting method (100) of 2 non-rectangulardecorative patterns (208, 209) on a flexible sheet (303), as decorationlayer, whereon copies of the 2 non-rectangular decorative patterns (208,209) are arranged and printed. The nesting method (100) nested adecorative pattern (208) in two copies and a decorative pattern (209) in4 copies. To minimize the waste of the decoration layer, 3 copies of thedecorative pattern (209) and 1 copy of the decorative pattern (208) is180 degrees rotated.

FIG. 4 illustrates a nesting method (100) of six decorative patterns(201, 202, 203, 204, 205, 206) on a flexible web (301), as decorationlayer, whereon the nested decorative patterns (201, 202, 203, 204, 205,206) are printed. Only a part of the flexible web material (301) isshown. The nesting method (100) nested a decorative pattern (206) withthree copies. The six decorative patterns (201, 202, 203, 204, 205, 206)are added in a nesting queue (150). A single pass inkjet printer, notshown in the illustration, has a failure zone (400) in its printingzone. The nesting method prevents the nesting of the decorative patternsin the failure zone (400) of the printing zone. The waste of decorationlayer is minimized in the nesting method by ninety degrees rotating of acopy of a decorative pattern (205).

FIG. 5 illustrates the adding of a bleed area (801) to a non-rectangulardecorative pattern (800) by choking the content area of thenon-rectangular decorative pattern (800).

FIG. 6 illustrates the adding of a bleed area (801) to a non-rectangulardecorative pattern (800) wherein the bleed area (801) is filled with thebackground colour of the decorative pattern (800).

FIG. 7 illustrates the adding of a bleed area (801) to a non-rectangulardecorative pattern (800) wherein the content of the decorative pattern(800) is extended until the external edges of the bleed area (801).

FIG. 8 illustrates the adding of a bleed area (801) to a non-rectangulardecorative pattern (800) wherein the bleed area (801) is filled with agradient from the background color to the contrast color of thedecorative pattern (800).

FIG. 9 illustrates the adding of a bleed area (801) to a non-rectangulardecorative pattern (800) wherein the bleed area (801) is filled withcloned pixels of the decorative pattern (800).

FIG. 10. illustrates the obtained decorative workpiece (7) by theinvention in a perspective view of decorative workpiece (7) and FIG. 11is a cross section at a larger scale along the line (4) in FIG. 10.

FIG. 10 and FIG. 11 illustrate the obtained decorative panel (7) by theinvention can have the shape of a rectangular and oblong laminate floorpanel, with a pair of long sides (27-28) and a pair of short sides(29-30) and having an HDF or MDF substrate (8). In this case the panel(7) is at long at least the long sides (27-28) with coupling means (31)allowing to lock the respective sides (27-28) together with the sides ofa similar panel both in a direction (R1) perpendicular to the plane ofthe coupled panels, as in a direction (R2) perpendicular to the coupledsides and in the plane of the coupled panels. As illustrated in FIG. 11such coupling means or coupling parts can basically have the shape of atongue (32) and a groove (33), provided with additional cooperatinglocking means (34) allowing for said locking in the direction (R2).

FIG. 10 and FIG. 11 illustrate a decoration layer (1) for incorporationin a decorative panel, obtainable by means of a method in accordancewith the invention. The decoration layer (1) comprises a paper sheetprovided with thermosetting resin. The thermosetting resin satisfies orfills the paper core. The paper layer has been provided with a digitallyprinted decorative pattern (5).

FIG. 12 shows the prior art production process for manufacturingdecorative panels, wherein a paper manufacturer (11) supplies a paperroll (12) to a decor printer (13) using gravure printing (14) or inkjetprinting (15) in order to deliver a decor paper roll (16) to a warehouse(17) of a floor laminate manufacturer (20). Depending on the marketdemand, the floor laminate manufacturer (20) selects one of thedifferent decor rolls in his warehouse (17) to impregnate (18) and tocut to a size (19) for being heat pressed and finished into ready-to-usefloor laminate (21).

FIG. 13 shows a production process for manufacturing decorative panels,wherein a paper manufacturer (11) supplies a paper roll (12) directly toa floor laminate manufacturer (20) who impregnates (18) the paper roll(12), cuts to a size (19) for being inkjet printed (15) and then heatpressed and finished into ready-to-use floor laminate (21). The order ofcutting to size (19) and inkjet printing (15) may also be reversed, i.e.printing on a impregnated paper roll before cutting to sheets.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Content Extension Area

To compensate inaccuracies in the printing process and/or finishingprocess and/or provide extension to a decorative pattern to mount adecorative workpiece, in, for example three-dimensional object content,extension areas have to be designed in a decorative pattern beforefinishing the decorative workpiece.

Examples of content extension areas are:

-   -   glue area: an area that will be glued afterwards while mounting        the decorative workpieces to a finished product;    -   connect area: an area to provide means that will be attached        while mounting the decorative workpieces to a finished product.        An example of such means is a tongue-and-groove profile on a        decorative workpiece;    -   folding area: an area that will be folded and/or attached while        mounting the print to a finished product. For example flaps that        are needed to fold a flexible decorative workpiece, such as a        vinyl tile to a box or around stair;    -   bleed area: Several finishing processes are used in the        manufacturing of decorative workpieces such as die cutting, kiss        cutting, drill cutting, creasing, perforating, foil stamping,        embossing, hi-die cutting, guillotine cutting, wet or dry        laminating, V-cutting, embossing with digital embossing plate,        tongue-and-groove profile producing. These finishing processes        may have inaccuracies while manipulating the printed decorative        patterns and/or the manufactured decorative workpieces and        that's why a bleed area added to a decorative pattern may be        needed.

In FIG. 11 a connect area, as content extension area may be added to thedecorative pattern (5) for the tongue (32) and the locking mean (34) atthe groove (33) by expanding the content area of the decorative patternprior printing on the decoration layer (1):

-   -   at the side of the tongue (32) expanding in 1 dimension by the        distance (811), also called the tongue distance; and    -   at the side of the groove (33) expanding in 1 dimension by the        distance (810), also called the groove distance.

In FIG. 11 a bleed area, as content extension area, may be added to thedecorative pattern (5) to compensate inaccuracies in the printing and/orfinishing process:

-   -   at the side of the tongue (32) expanding in 1 dimension by the        bleed distance (807)    -   at the side of the groove (33) expanding in 1 dimension by the        bleed distance (805).

Bleed Area

A bleed area is an example of a content extension area that is createdto compensate inaccuracies in the printing process and/or finishingprocess such as cutting or producing tongue-and-groove profile to adecorative workpiece. This bleed area may be created by expanding thepresent content area of the decorative patterns with several millimetres(for example from 2 or 5 mm). The size of expanding the content area toa bleed area depends on the inaccuracies of the printing process and/orfinishing process (for example cutting).

The adding of a bleed area for a decorative pattern, which may beoverruling the existing bleed area of a decorative pattern, ispreferably done automatically in the preferred embodiment. This methodis also called choking the content area.

This distance that expands the content area to create the bleed area iscalled bleed distance. The bleed distance is preferably from 0.1 mm to10 mm, more preferably from 0.3 mm to 8 mm and most preferably from 0.3to 15 mm. The bleed distance may be determined in the preferredembodiment but it is more preferred to determine the bleed distanceautomatically based on the inaccuracies of the printing and/or finishingprocess. It is most preferred that the bleed distance is determineddepending on the content of the determined decorative patterns.

In a preferred embodiment with a nesting method, the bleed distance maybe different between two nested decorative patterns on a decorationlayer.

The bleed area adding preferably creates a content extension area thathas the same shape as the content area with the same centre as thecontent area but the shape is larger than the content area wherein thecentre the point is in the content area with equal distances from allpoints on the boundary of the content area.

A preferred embodiment may transform a bleed area of a determineddecorative pattern to an optimized bleed area based on the finishingand/or cutting process.

A bleed area is an area which is not visible anymore in the decorativeworkpiece at the end of the manufacturing. In a bleed area one or moremarks may be added wherein a mark is preferably

-   -   a cut mark; and/or    -   a saw mark; and/or    -   an alignment mark; and/or    -   a control mark; and/or    -   an information code of the first decorative pattern; and/or    -   an information code of the print parameters of the first        decorative pattern; and/or    -   an information text of the first decorative pattern; and/or    -   an information text of the print parameters of the first        decorative pattern. The reading of a code by an operator or a        reading device gives the information, for example how to        manufacturing the decorative workpieces in the steps after the        printing of the mark or how to control the step of printing to        enhance the print quality. Such information enhances the        manufacturing timings and/or manufacturing qualities.

Examples of marks in the manufacturing of decorative workpieces aredisclosed in EP2556962 (HUELSTA WERKE HUELS KG).

A preferred embodiment may add a mark to a content extension area andmore preferably to a bleed area of a decorative pattern.

A more preferred embodiment may add a colored mark to a contentextension area, more preferably a bleed area of a decorative patternwherein the color of the mark may have a color difference with thecontrast color of the decorative pattern between zero delta E in CIELaband 10 delta E in CIELab to enhance the readability of the mark.

More information about luminance, hue of colours, color differences,CIELab, CIEXYZ is disclosed in DR. R. W. G. HUNT. The reproduction ofcolour. 4th edition. England: Fountain Press, 1987.

Bleed Area Filling

In stead off expanding the content of the decorative pattern to fill thebleed area, other bleed area fillings may be comprised in the adding ofa bleed area to a decorative pattern. Preferably image content of thedecorative pattern is used to fill the bleed area. This compensatesinaccuracies in the printing process and/or finishing process evenbetter than remaining the bleed area empty, an empty bleed area becomesvisible if the finishing process is not accurate enough.

The bleed area filling may selected from:

-   -   filling the bleed area with the background colour of the        decorative pattern; or    -   filling the bleed area with a gradient of the background colour        of the decorative pattern; or    -   filling the bleed area with a gradient of the background color        of the decorative pattern to the contrast color of the        decorative pattern.    -   cloning pixels of the decorative pattern in the bleed area; or    -   mirror-wise cloning pixels, also called adverse cloning pixels,        of the decorative pattern in the bleed area.

Mirror-wise cloning of pixels in a bleed area means that the bleed areawith the cloned pixels is a reflection of the decorative pattern aroundthe edge of the decorative pattern or more preferably that the bleedarea with the cloned pixels is a reflection around the edge of thedecorative pattern and wherein the reflection is a an area at the edgein the decorative pattern.

Nesting

A nesting method is a method to arrange a set of decorative patterns,whether or not with their content extension areas, on a decoration layerto reduce the waste of the decoration layer and to shorten theproduction time. The set of decorative patterns becomes nesteddecorative patterns on the decoration layer after applying the nestingmethod. In a nesting method it is obvious that the amount of decorativepatterns in the set of decorative patterns is two or more. Preferablyminimal two of the decoration patterns in the set of decorative patternsare selected from a different decoration image.

A processing apparatus which executes nesting processing is done bysoftware which implements a computerized nesting method. Such softwareis called nesting software. The processing apparatus is preferably acomputer with appropriate means to store decorative patterns such asmemory and appropriate means to execute the nesting method such as aCPU.

The dimensions of the set of decorative patterns may be different inwidth and length for each decorative pattern.

The processing apparatus may comprise one or more Graphic ProcessingUnit (GPU) for faster calculation of steps in the nesting method andthus gives a higher productivity of the manufacturing of the decorativeworkpieces. The GPU may also be use for image manipulations such asrotation, color conversion of decorative patterns in the nesting method.

A nesting method may comprising the following steps:

-   -   determining the amount of copies that have to be nested of a        decorative pattern.    -   ordering decorative patterns based on nesting priorities that        where given as input while determining decorative patterns in        the nesting queue in the preferred embodiment of the nesting        method; and/or    -   visualizing statistics of the nesting performance, for example        how much free space is still available on the decoration layer;        and/or    -   grouping a part of decorative patterns together on a part of a        decoration layer because they have to be cut together; and/or    -   calculating the minimal distance and/or maximal distance between        the content area and/or content extension area of two nested        decorative patterns; and/or    -   using a defined minimum interspace distance, also called margins        while nesting decorative patterns so the minimal distance        between the content area or content extension area of decorative        patterns is equal or larger than the defined minimum interspace        distance; and/or    -   creating space to add control marks and codes on the decoration        layer.

The nesting method may be based on the shape and/or dimension of thecontent extension area and the size of the decoration layer butpreferably it is based on the shape and/or dimension of the content areaand the size of the decoration layer to reduce more the waste of asubstrate and to shorten the production time. If bleed areas as contentextension areas of two decorative patterns are overlapping the bleedarea of both decorative patterns may be recalculated to non-overlappingbled areas. For example the overlapping area of both bleed areas may bedivided in two parts and each part is added to a content extension areaof the decorative pattern.

The nesting method may be rectangular nesting but it is more preferablytrue shape nesting.

Preferably the nesting method orders the decorative patterns based onthe dimensions of the content area or content extension area beforefilling the decoration layer.

Preferably the nesting method rotates the decorative patterns tooptimize the reducing of waste. To minimize the calculation of nesting,it is preferred to rotate the decorative pattern in incremental stepswhile trying to fit a decorative pattern on a decoration layer.

To create variances in the decorative patterns the nesting method maymirror, rotate, change the color, preferably the hue, or change thecolorway of a decorative pattern from the set of decorative patterns.

A colorway is a combination of several different combinations of coloursin which a decorative pattern is printed.

The nesting method may add a bleed area to a decorative pattern from theset of decorative patterns and preferably fill the bleed area with imagecontent of the decorative pattern. If the decorative pattern had alreadya bleed area the nesting method may replace the bleed area by a newbleed area and preferably fill the bleed area with image content of thedecorative pattern.

The nesting method may also arrange in the same arrangement as on thedecoration layer the relief contents of the set of decorative patternsso there is a correct match between the nested decorative patterns onthe decoration layer and the nested relief contents that is provided bya digital relief apparatus.

Deco Digital Workflow System

To manage the printing of decorative patterns by one or more digitalprint devices in a method of manufacturing deco workpieces, thepreferred embodiment may comprise deco digital workflow system, forexample for determining decorative patterns, nesting decorativepatterns, digital printing nested decorative patterns on a decorationlayer and/or digital cutting nested decorative workpiece with printednested decorative patterns to separated decorative workpieces.

To handle the mixture of decorative patterns, nested decorative patternsa deco digital workflow system is important, for example to know fromeach nested decorative workpiece the correct nested decorative patterns.This may be monitored by reading marks on the nested decorativeworkpiece wherein the readings are feed back to the deco digitalworkflow system.

The deco digital workflow system comprises preferably a managementinformation system (MIS) to provide information that the manufacturingof decorative workpieces require to manage themselves efficiently andeffectively and to analyze and to facilitate strategic and operationalactivities.

In a preferred embodiment a part of a decorative pattern is digitalprinted on a package wherein a decorative workpiece, whether or not withother decorative workpieces, is wrapped in the package and wherein thedecorative workpiece carries the decorative pattern. Prior the wrappingof the decorative workpieces the decorative workpieces may be collected.The collected decorative workpieces are preferably cut out of a nesteddecorative workpiece. The digital printing of the package is preferablymanaged by a deco digital workflow system.

The deco digital workflow system may manage the forming of relief on adecorative workpiece or a nested decorative workpiece by digital reliefapparatus.

Deco Storefront

In a preferred embodiment a cloud-based web-to-print solution may becomprised to enable decorative workpiece service providers or decorativeworkpiece buyers to create and manage online stores for manufacturing ofdecorative workpieces which is called a deco storefront.

Preferably a deco storefront is marketed as a hosted cloud service sothere is no high initial investment needed in servers, software,databases or expensive symmetrical internet connections. This reducesthe cost of deploying stores and improves their time-to-market.

The deco storefront may have an easy manageable store centre which isthe central hub from which stores are set up and orders are tracked. Itsdashboard preferably provides instant feedback about incoming orders andthe status of orders that are in progress.

The deco storefront preferably comprises an online editor whereindecorative workpiece service providers or editors may design or editdecorative patterns or add decorative images. This gives the ability tothe decorative workpiece service providers an innovative way of creatingpersonalized decorative workpieces.

The integration of the deco storefront in a deco digital workflow systemmay increase the efficiency by saving time in for example theautomatically downloading and processing orders of decorativeworkpieces.

Nesting Queue

The nesting method may have a step of determining decorative patternsthat have to be arranged on one or more decoration layers; and/or mayhave a step of determining decorative images whereof one or moredecorative patterns are taken as region-of-interests from the decorativeimage to be arranged on one or more decoration layers

The determination is preferably done by adding the decorative patternsand/or decorative images in a queue, also called the nesting queue.

The nesting method preferably provides a method to visualize the nestingqueue and the arrangement of the determined decorative patterns on adecoration layer. Preferably the visualization is by visualizingthumbnails of the content of the decorative patterns and more preferablythe visualization is by visualizing information of the determineddecorative patterns such as decorative pattern name, creator name,amount of copies that need to be nested or the preferred rotation.

Nesting-on-the-Fly

To reduce the waste of a decoration layer which is a flexible webmaterial printed by a digital printer, the priority of arranging a setof decorative patterns on the decoration preferably has a firstpriority: arranging across the flexible web material and as secondpriority: arranging along the flexible web material.

The digital printer, preferably an inkjet printer, may perform thisnesting method while printing already arranged decorative patterns,whether or not with their content extension areas, from the set ofdecorative patterns on the decoration layer to increase the productiontime of nested decorative workpieces. This preferred nesting method isalso called nesting-on-the-fly. Preferably nesting-on-the-fly comprisesthe merging of image content from a part of the set of decorativepatterns to minimize the waste across the flexible web material, asdecoration layer, while printing. The merging of the image content ofdecorative patterns is easy established because decorative patterns aredefined in a raster graphics format. Preferably the merging of the imagecontent of decorative patterns comprises the step of merging thescan-lines of the decorative patterns. A scan-line is one line, or row,in a raster graphics format.

The nesting-on-the-fly method may be performed by workstations with afast CPU such as, an Intel Xeon w3550 which has 4 cores at 3.06 GHz.Preferably these nesting-on-the-fly workstations comprises more than oneCPU to follow the print speed to print the nested decorative patternswhile performing the nesting-on-the-fly, more preferably more than 4CPU's to follow the print speed to print the nested decorative patternswhile performing the nesting-on-the-fly and most preferably more than 8CPU's to follow the print speed to print the nested decorative patternswhile performing the nesting-on-the-fly.

The nesting-on-the-fly workstations may comprise to calculate steps inthe merging of the nested decorative patterns one or more GraphicProcessing Units (GPU).

Preferably the set of decorative patterns is a dynamic set whereindecorative patterns may be added while performing nesting-on-the-fly.Because nesting-on-the-fly makes the possibilities of nesting moredynamically: for example a decorative pattern which is not yet arrangedon the decoration layer may get a higher nesting priority and thus shallbe nested earlier on the decoration layer. Also in nesting-on-the-fly adecorative pattern which is not yet arranged on the decoration layer maybe removed if, for example the production of the decorative pattern isnot needed anymore.

Nesting-on-the-fly method is preferably performed in the manufacturingof decorative workpieces wherein the nested decorative patterns areprinted by a single pass inkjet printer.

Nesting-on-the-fly method may comprising a rectangular nesting method ortrue-shape nesting method.

Rectangular Nesting

The method of rectangular nesting uses a rectangle around the shape ofthe content area or content extension area, such as bleed area, of adecorative pattern with largest height and width. The shape of thecontent area or content extension area, such as bleed area, of thedecorative pattern is than treated as the geometry of the rectangle andnot the real shape of the content area and/or content extension area,such as bleed area, of the decorative pattern when placing thedecorative pattern on the sheet while nesting. This method is a fastnesting method and reduces the waste of a substrate.

True Shape Nesting

The method of true shape nesting identifies a portion of the actualshape of the content area or content extension area, such as bleed area,of a decorative pattern. For example the left side and bottom of theactual shape of the content area or content extension area, such asbleed area, of a decorative pattern is examined to determine how well itfits with adjacent shape of content area's or bleed area's of otherdecorative patterns. The top and the right side of the actual shape ofthe content area or content extension area, such as bleed area, of adecorative pattern are ignored until another decorative pattern isplaced next to it.

Preferably while using true shape nesting in a preferred embodiment thedecorative patterns that are already placed on the decoration layerremain stationary and only newly decorative patterns are considered forarrangement and rotation. The purpose of this heuristic rule is toeliminate most of the calculation of nesting. This heuristic rule issometimes called “first fit”.

The true shape nesting preferably comprises the following steps

a) ordering the decorative patterns from largest to smallest surface ofcontent area or bleed area;

b) placing the largest decorative pattern on the decoration layer;

c) rotating the decorative pattern to the orientation that brings itclosest to a corner of the decoration layer, also called the nestingcorner;

d) placing the next largest decorative pattern on the decoration layer;

e) rotating the decorative pattern to the orientation that brings itclosest to the nesting corner;

f) repeating steps d) and e) until all decorative patterns are nested oruntil no more decorative patterns will fit on the decoration layer.

True shape nesting may take the whole shape of the content area orcontent extension area, such as bleed area, of a decorative pattern intoaccount while optimal filling a decoration layer and preferably multipledecorative patterns are observed to fill a decoration layer without atime consuming trial and error process of rotating decorative patternsin hundreds of small increments to check for a fit.

Another preferred method of true shape nesting is a neighbourhood searchnesting method. An example of a neighbourhood search nesting method isdisclosed in “Fast Neighborhood Search for the Nesting Problem” by BENNYKJAER NIELSEN et al, in Technical Report 03/03, Department of ComputerScience, University of Copenhagen and this preferred method of trueshape nesting is optimized with method to solve the travelling salesmanproblem (TSP) such as Guided Local Search (GLS) and Fast Local SearchFLS). Theory and methodology about these guided local search and fastlocal search and the travelling salesman problem is disclosed in “Guidedlocal search and its application to the travelling salesman problem” byCHRISTOS VOUDOURIS et al, in European Journal of Operational Research113 (1999) p469-499.

True shape nesting may nest a group of decorative patterns that have abest fit together by the shape of their content area's or contentextension area's independently of the decoration layer whereon is nestedand than nest this group of decorative patterns with the otherdecorative patterns.

Graphic Processing Units

Graphic Processing Units (GPU's) have been used to render computergraphics for years. Nowadays they are also used for general-purposetasks due to their highly parallel structure, making them more efficientthan Central Processing Units (CPU's).

GPU's can be combined with CPU's to achieve greater performance. In thisway, serial parts of the code would run on the CPU and parallel partswould do it on the GPU. While CPU's with multiple cores are availablefor every new computer and allow the use of parallel computing, theseare focused on having a few high performance cores. On the other hand,GPU's have an architecture consisting of thousands of lower performancecores, making them especially useful when large amount of data have tobe processed.

One of the most popular tools available on the market of GPU computingis CUDA. CUDA is a parallel computing platform and programming modelcreated by Nvidia™ and available only for their GPU's. The mainadvantage of CUDA is its ease of use, using the language known as CUDA Cwhich is essentially an extension of C, with similar syntax and veryeasy to integrate in a C/C++ environment.

The CUDA processing flow is as follows: The needed data is first copiedfrom the main memory to the GPU memory ({circle around (1)}), the CPUsends an instruction to the GPU ({circle around (2)}), the GPU executesthe instruction in all the parallel cores at the same time ({circlearound (3)}), and the result is copied back from the GPU memory to themain memory ({circle around (4)}).

CUDA parallel execution units consist of threads grouped into blocks.Combining the use of blocks and threads the maximum number of availableparallel units can be launched, which for the latest GPU's can be morethan 50 million. Even though this is a great amount of parallelcapability, there are some cases where data might exceed the limit. Inthose cases, the only possibility is to iterate through the grid ofmillions of parallel units as many times as needed till all the data isprocessed.

Decorative Image

A decorative image is an image representing wood, stone, rock or fantasypattern.

A decorative image is achieved by suitable commercially availablehardware, such as scanning a photograph or taking an image by a digitalcamera, and commercially available software, such as Adobe Photoshop™ tomanipulate and create decorative images.

The content of a decorative image is preferable defined in rastergraphics format such as Portable Network Graphics (PNG), Tagged ImageFile Format (TIFF), Adobe Photoshop Document (PSD) or Joint PhotographicExperts Group (JPEG) or bitmap (BMP) but more preferably in vectorgraphics format, wherein the decorative image as raster graphics formatis embedded. Preferred vector graphics formats are Scale Vector Graphics(SVG) and AutoCad Drawing Exchange Format (DXF) and most preferably thedecorative image is embedded in a page description language (PDL) suchas Postscript (PS) or Portable Document Format (PDF).

A decorative image may be stored and/or loaded as one or more files on amemory of a computer. The preferred embodiment may comprise a method toload a decorative image into a memory of a computer.

A two-dimensional or three-dimensional representation of the relief,also called relief content of a decorative image, may be embedded in thedecorative image. The two-dimensional representation of the relief onlydefines a fixed impression height of the relief and a three-dimensionalrepresentation of the relief defines variable impression heights.

Decorative Patterns

The decorative pattern is a region-of-interest from a decorative imageso variances in decorative patterns may be achieved by selectingdifferent region-of-interests in the decorative image. The ratio of thearea of such a region-of-interest as decorative pattern and the area ofthe decorative image is preferably between 50% and 100%, more preferablybetween 10% and 100% and most preferably between 1% and 100%. The areawith the content of the region-of-interest as decorative pattern is alsocalled content area. The size of the region-of-interest and thus thedecorative pattern may have a width between 50 mm and 4000 mm, and alength between 100 mm and 6000 mm or more.

A two-dimensional or three-dimensional representation of the relief forthe decorative pattern, also called relief content of a decorativepattern, may be embedded in the decorative pattern. The two-dimensionalrepresentation of the relief only defines a fixed impression height ofthe relief and a three-dimensional representation of the relief definesvariable impression heights.

A decorative pattern is preferable rectangular shaped but it can also betriangular, quadratic, rectangular, heptagonal, pentagonal andoctagonal, or elliptical shaped. A decorative pattern may have a sidewith 1 or more curved parts. The advantage of rectangular shapeddecorative patterns is the ease of cutting to a decorative workpiece,which may be a step of the preferred embodiment. Rectangular ornon-rectangular shaped decorative patterns may be cut by cuttingplotters. The use of cutting plotters is more time-consuming butnon-rectangular shaped decorative patterns expand the amount ofassembling creations of decorative workpieces such as mosaic flooringwith laminates, or design furniture.

The content of a decorative pattern is preferable defined in rastergraphics format such as Portable Network Graphics (PNG), Tagged ImageFile Format (TIFF), Adobe Photoshop Document (PSD) or Joint PhotographicExperts Group (JPEG) or bitmap (BMP) but more preferably in vectorgraphics format, wherein the decorative pattern as raster graphicsformat is embedded. Preferred vector graphics formats are Scale VectorGraphics (SVG) and AutoCad Drawing Exchange Format (DXF) and mostpreferably the decorative pattern is embedded in a page descriptionlanguage (PDL) such as Postscript (PS) or Portable Document Format(PDF).

A decorative pattern may be stored and/or loaded as one or more files ona memory of a computer. The preferred embodiment may comprise a methodto load a decorative pattern to a memory of a computer.

A decorative pattern may be an element of a queue of decorative patternsthat is generated from variable-data printing (VDP), also known asvariable-information printing, which is a form of digital printing,including on-demand printing, in which elements such as text, graphicsand images may be changed from one printed piece to the next, withoutstopping or slowing down the printing process and using information froma database or external file. The generated decorative patterns from avariable-data printing method may be nested on one or more decorationlayers.

The background color of a decorative pattern is defined by the tone ofthe decorative pattern. The tone in a decorative pattern may becalculated by determine the color in the color histogram of thedecorative which appears the most in the decorative pattern. Thebackground color is also called the wood color if the decorative patternrepresents a wood.

The contrast color of a decorative pattern is a color in the decorativepattern which has the highest colour difference with the backgroundcolor such as the highest delta E in CIELab.

If the decorative pattern represents a wood the density of wood grainlines is defined by the density of the wood nerves. A higher density ofwood grain lines may be caused by smaller growth rings in the wood.

Selecting Region of Interest

In a preferred embodiment the decorative pattern is determined from adecorative image based on the content in the decorative image. Theselection may comprise an image analysis on the content in thedecorative image such as wood grain imperfections detection andpreferably comprises an image analysis on knots and/or cracks, as woodgrain imperfection, in the decorative image. The image analysis maycomprise fast Fourier transformations (FFT), histogram calculations andfiltering methods.

By determining the amount of knots or cracks, the selection may avoidthat the amount of knots in a region-of-interest of the decorative imageis larger than the determination; and/or

by determining the size of a knot or cracks, the selection may avoidthat the size in diameter of a knot in a region-of-interest of thedecorative image is larger than the determination; and/or

by determining the maximum distance from a knot or crack to the edge ofa region-of-interest may avoid that a knot or crack in aregion-of-interest of the decorative image is positioned nearby at theedge of the region-of-interest; and/or

by determining the density of the wood grain lines, the selection mayavoid that the density of the wood grain lines in a region-of-interestof the decorative image is smaller than the determination or larger thanthe determination.

These determination results in easier finishing of a workpiece such ascutting and digital embossing because a knot and crack influences theamount of ink on the position of printed knots or cracks on thedecoration layer which, for example may give delaminating issues of aworkpiece.

The apparatus that performs the image analysis on a decorative image ordecorative pattern may comprise one or more Graphic Processing Units(GPU).

Decoration Layer

A decoration layer is a layer comprised in a decorative workpiece or anested decorative workpiece. The decoration layer carries a decorationlayer in a decorative workpiece or the decoration layer carries two ormore decorative patterns in a decorative workpiece. If the decorationlayer carries two or more nested decorative pattern in a decorativeworkpiece, the decorative workpiece is called a nested decorativeworkpiece. The nested decorative workpiece is cut up to a plurality ofdecorative workpieces. The nested decorative workpiece is preferably cutby a cut device such as a saw but preferably by a cutting plotter toseparate decorative workpieces with each of the decorative pattern thatwere nested.

The size of a decoration layer if it is a sheet may have a width between50 mm and 4000 mm and a length between 100 mm and 6000 mm. If thedecoration layer is a web that width may between 50 mm and 4000 mm.

The decorative pattern printed on the decoration layer may be printed bya digital printer, preferably an inkjet print device.

The decorative pattern may be printed directly on wood-based panels asdecoration layer, more preferably be printed directly on chipboard,particleboard, medium density fiber board panel (MDF), high densityfiber board panel (HDF) or a substrate consisting of or essentially madeof wood particleboard and most preferably be printed on a rigid sheet,flexible sheet or a flexible web material.

Rigid sheets may be selected from hard board, PVC, carton, wood and woodwith an ink receiver. The rigid sheets preferably have a thickness from3 mm to 3 centimetres and more preferably have a thickness from 3 mm to5 centimetres.

Flexible sheet may be selected from cellulose-based material, paper,impregnated paper, resin pre-impregnated paper, transparency foils, PVCsheets with thickness from 0.5 micrometer to 100 micrometers andpreferably from 0.5 micrometer to 50 micrometers.

Flexible web material may be selected from cellulose-based material,paper, vinyl, fabrics, PVC or textile which is used in so calledroll-to-roll digital printers.

The decoration layer, as flexible sheet or flexible web material, ispreferably a paper with a weight from 50 to 150 g/m².

In a preferred embodiment the manufacturing of the decorative workpiecescomprises the step of resin impregnation of the decoration layer and ina more preferred embodiment the decoration layer is impregnated priordigital printing of a decorative pattern on the substrate and in a mostpreferred embodiment the decoration layer is in a first step impregnatedand in a second step coated with an ink receiver prior inkjet printingthe decorative pattern on the ink receiver by an inkjet print device.

Decoration Paper

A decoration paper is a decoration layer, which is also called decopaper. In a preferred embodiment the decoration layer is a decorationpaper.

The decoration paper preferably has a weight of less than 150 g/m²,because heavier decoration paper is hard to impregnate all through theirthickness with a thermosetting resin. Preferably said decoration paperhas a paper weight, i.e. without taking into account the resin providedon it, of between 50 and 130 g/m² and preferably between 70 and 130g/m². The weight of the paper cannot be too high, as then the amount ofresin needed to sufficiently impregnate the paper would be too high, andreliably further processing the printed paper in a pressing operationbecomes badly feasible.

Preferably, the decoration paper has a porosity according to Gurley'smethod (DIN 53120) of between 8 and 20 seconds. Such porosity allowseven for a heavy sheet of more than 150 g/m² to be readily impregnatedwith a relatively high amount of resin.

Suitable decoration paper having high porosity and their manufacturingare also disclosed by U.S. Pat. No. 6,709,764 (ARJO WIGGINS).

The paper for the decoration layer is preferably a white paper and mayinclude one or more whitening agents, such as titanium dioxide, calciumcarbonate and the like. The presence of a whitening agent helps to maskdifferences in colour on the core layer which can cause undesired coloureffects on the colour pattern.

Alternatively, the paper for the decoration layer may be a bulk colouredpaper including one or more colour dyes and/or colour pigments. Besidesthe masking of differences in colour on the core layer, the use of acoloured decorative paper reduces the amount of inkjet ink required toprint the colour pattern. For example, a light brown or grey paper maybe used for printing a wood motif as colour pattern in order to reducethe amount of inkjet ink needed.

In a preferred embodiment, unbleached Kraft paper is used for a brownishcolored decoration paper in the decoration layer. Kraft paper has a lowlignin content resulting in a high tensile strength. A preferred type ofKraft paper is an absorbent Kraft paper of 40 to 135 g/m² having a highporosity and made from clean low kappa hardwood Kraft of gooduniformity.

Resin Impregnation Method

In a preferred embodiment the decoration layer, which carries adecorative pattern, is provided with an amount of resin, moreparticularly is soaked in resin and/or is impregnated with resin, alsocalled a resin impregnation method.

This resin impregnation method is the preferred method in the preferredembodiment of manufacturing of decorative workpieces wherein decorativeworkpieces are laminate panels, in the first place laminate floorpanels, however, in the second place also laminate panels for otherpurposes, such as for furniture, partition walls and the like. Thedecorative workpieces manufactured with a resin impregnation method mayalso be profiles used in furniture's or skirting boards.

Preferably the resin is a thermosetting resin and more preferably thethermosetting resin is a melamine based resin, more particularly amelamine formaldehyde based resin with formaldehyde to melamine ratio of1.4 to 2. Other thermosetting resins may be ureum-formaldehyde basedresins and phenol-formaldehyde based resins.

The resin impregnation method may be a high pressure decorativeworkpiece method such as high pressure laminate method (HPL) or directpressure workpiece method such as direct pressure laminate method (DPL).Direct pressure workpiece method is a method of fusing a surface, innerlayers and backing layers in a single pressing operation to manufacturea workpiece or nested workpiece.

Examples of resin impregnation methods for decorative workpieces aredisclosed in WO2009153680 (FLOORING INDUSTRIES).

In a preferred embodiment with a resin impregnation method, it maycomprise method of applying a relief on the top layer of the decorativeworkpiece with a digital relief apparatus.

Overlay

In the manufacturing of a decorative workpiece with resin impregnationmethods an overlay may be used to protect the decorative pattern and toimprove the abrasion resistance of the decorative workpiece. In apreferred embodiment the decoration layer is at the same time theoverlay in the manufacturing of the decorative workpiece and wherein thedecorative pattern is printed, preferably mirrored printed, on thebottom of the overlay.

Digital Relief Apparatus

Preferably a relief may be formed on the decorative workpiece or nesteddecorative workpiece. Such relief can be provided in accordance with theprinted decorative pattern or printed nested decorative patterns. In thecase of an imitation of wood, the relief may imitate, for example, anatural relief of wood, in the form of impressions representing thepores and the like, in accordance with the printed wood decorativepattern. In the case of an imitation of stone, also the natural reliefof a stone species can be imitated in accordance with the printeddecorative pattern, and/or impressions can be formed for representinglower-situated cement grout lines and the like. The relief is formed bya digital relief apparatus.

The relief may be formed by jetting the relief as cured inkjet droplets,jetted by an inkjet print device, and more preferably UV cured inkjetdroplets. The relief formed by the cured inkjet droplets may be printedon top of other cured or pin-cured inkjet droplets to create variancesof height in the relief.

Most preferably the relief is formed by pressing a digital embossingplate against the top layer of the decorative workpiece or nesteddecorative workpiece.

Digital Embossing Plate

A digital embossing plate is a plate which comprises elevations that canbe used to form a relief on decorative workpiece by pressing the digitalembossing plate against the top layer of the decorative workpiece ornested decorative workpiece. The elevations are cured inkjet droplets,jetted by an inkjet print device, and most preferably UV cured inkjetdroplets. The elevations are preferably formed by printing and curinginkjet droplets on top of already cured or pin-cured inkjet droplets.The plate is preferably stiff by using metal or hard plastic.

An alternative of a digital embossing plate may be a digital embossingcylinder which is a cylinder that comprises the elevations to form arelief on decorative workpieces by pressing and rotating the digitalembossing cylinder against the top layer of the decorative workpiece ornested decorative workpiece. The elevations on the digital embossingcylinder are cured inkjet droplets, jetted by an inkjet print device,and most preferably UV cured inkjet droplets. The elevations arepreferably formed by printing and curing inkjet droplets on top ofalready cured or pin-cured inkjet droplets.

Digital Print Device

Today, more and more digital print devices are developed for thereproduction of decorative patterns. Several digital printingtechnologies are used such as electro-photography, thermal transfer, dyesublimation and ink jet systems to name a few. In this document adigital print device may be referred as digital printer.

An example of a digital print device is disclosed in EP2565778 A(BROTHER IND LTD) where the digital printer performs printing based onoperation in a host connected to a USB-port and wherein a printprocessing method is executed by the digital printer.

The decorative patterns are preferably printed by a digital printdevice, more preferable by an inkjet print device, also called an inkjetprinter and most preferably by a single pass inkjet print device, alsocalled a single pass inkjet printer.

The inkjet print head in an inkjet print device normally scans back andforth in a transversal direction across the moving decoration layer.Often the inkjet print head does not print on the way back.Bi-directional printing is preferred in the preferred embodiment forobtaining a high area throughput.

Another preferred printing method is by a “single pass printingprocess,” which can be performed by using page wide inkjet print headsor multiple staggered inkjet print heads which cover the entire width ofthe decoration layer. In a single pass printing process the inkjet printheads usually remain stationary and the substrate surface is transportedonce under the inkjet print heads.

A preferred print head for an inkjet printing system in a preferredembodiment is a piezoelectric head. Piezoelectric inkjet printing isbased on the movement of a piezoelectric ceramic transducer when avoltage is applied thereto. The application of a voltage changes theshape of the piezoelectric ceramic transducer in the print head creatinga void, which is then filled with ink. When the voltage is againremoved, the ceramic expands to its original shape, ejecting a drop ofink from the print head. However the manufacturing method according tothe present invention is not restricted to piezoelectric inkjetprinting. Other inkjet print heads can be used and include varioustypes, such as a continuous type.

More information about inkjet print devices is disclosed in STEPHEN F.POND. Inkjet technology and Product development strategies. UnitedStates of America: Torrey Pines Research, 2000. ISBN 0970086008.

Preferably in a preferred embodiment with nesting method may providing amethod to transfer the nested decorative patterns on one or moredecoration layers to a digital printer so it can be printed on a digitalprinter. The transfer of the nested decorative patterns is done byappropriate means, for example computer network or USB-port in aappropriate raster image format, vector image format or page descriptionlanguage such as PostScript (PS) or Page Description Format (PDF).

However, in a digital print device and especially in an inkjet printdevice, there are a number of fundamental weaknesses compared to theconventional print devices, such as rotogravure, especially when itcomes to the high-speed printing of decorative patterns on a decorationlayer for the manufacturing of decorative workpieces.

A part in the printing zone of a digital print device may fail to printon the decoration layer, such as malfunctions of a nozzle or inkjetprint head in an inkjet print device or malfunctions on a photoconductordrum in a xerography process of a digital print device. Or a part in theprinting zone of a digital print device may fail to print qualitative onthe decoration layer. Such parts in the printing zone are called afailure zone in the printing zone. A part in the printing zone which isnot a failure zone in the printing zone is called a quality zone in theprinting zone. In a preferred embodiment with a nesting method, thenesting method may prevent the printing of nested decorative patterns ina failure zone in the printing zone. The preferred embodiment with anesting method may nest a decorative pattern with its content extensionarea, such as bleed area or connect area, wherein the decorative patternis printed in the quality zones of the printing zone and a part of thecontent extension area, such as bleed area or connect area, ispositioned or printed in a failure zone in the printing zone.

The detection of failure zones in the printing zone may be done byvisual monitoring and measuring the print quality while printing thenested decorative patters on the digital print device and/or visualmonitoring and measuring marks, printed by the digital print device, onthe decoration layer. Preferably the visual monitoring is done byinspection cameras.

Cutting Plotter

Cutting plotter is a device to cut a decorative workpiece out of anested decorative workpiece. The most common cutting device is a digitalfinishing table, also called digital cutting table or table cutter. Thedigital finishing table may have a vacuum table that holds the nesteddecorative workpiece while finishing the nested decorative workpiece.

The cutting of the nested decorative workpiece is mainly done withrotary cutters but other technologies such as sharp knives, laser,water-jet, punches, shear blades, plasma cutting, ultrasonic knifes,milling tools and flame cutting can also be used.

An example of table cutter is disclosed in EP2455184 (MIMAKI ENGINEERINGCOMPANY) wherein a gantry moves over the bed in a first direction and ahead with cutting tools is moving along the gantry in a seconddirection.

The content area and/or content extension area, such as connect area orbleed area, of a nested decorative pattern in a nesting method may beconverted to cutting shapes which may be sent to the cutter plotter. Theconversion to cutting shapes may be a computerized method that may beloaded in a memory of a computer, connected to the cutting plotter, anddriven on the computer. The conversion to cutting shapes in a cuttingplotter to command the cutting tools to manufacture the correctdimensioned decorative workpiece may be a computerized method.

Preferably the nesting method may provide a method to transfer cuttingshapes to a cutting plotter in an appropriate format, for example DXF orPDF by appropriate means, for example network or USB-port.

A part in the cutting zone of a cutting plotter may fail to cut a nesteddecorative workpiece, such as malfunctions of a knife in a digital tablecutter. Or a part in the cutting zone of a cutting plotter may fail tocut qualitative a nested decorative workpiece. Such parts in the cuttingzone are called a failure zone in the cutting zone. The part in thecutting zone which is not a failure zone in the cutting zone is called aquality zone of the cutting zone. In a preferred embodiment with anesting method, the nesting method may prevent that a nested decorativeworkpiece shall be cut in a failure zone of the cutting zone.

The detection of failure zones in the cutting zone may be done by visualmonitoring and measuring the print quality while cutting the nesteddecorative patters on the cutting plotter and/or visual monitoring andmeasuring marks, printed by the cutting plotter, a nested decorativeworkpiece. Preferably the visual monitoring is done by inspectioncameras.

Decorative Workpiece

The decorative workpieces are preferably rigid or flexible panels, butmay also be rolls of a flexible substrate. In a preferred embodiment thedecorative workpieces are selected from the group consisting of kitchenpanels, flooring panels, furniture panels, ceiling panels and wallpanels.

A preferred decorative workpiece may contain an inkjet printedthermosetting resin impregnated paper having an ink acceptance layerincluding an inorganic pigment P and a polymeric binder B wherein theP/B ratio is larger than 1.5 and a colour pattern including a colourpigment C with a P/C ratio larger than 4.0 heat pressed with a corelayer and a protective layer, wherein the decorative workpiece isselected from the group consisting of flooring, kitchen, furniture andwall panels.

In a more preferred embodiment, the decorative workpiece includes atongue and a groove capable of achieving glue less mechanical join.

The decorative workpieces, especially decorative panels, may furtherinclude a sound-absorbing layer as disclosed by U.S. Pat. No. 8,196,366(UNILIN).

In a preferred embodiment, the decorative panel is an antistatic layeredpanel. Techniques to render decorative panels antistatic are well-knownin the art of decorative workpieces as exemplified by EP1567334(FLOORING IND).

In a preferred embodiment, the decorative panels are made in the form ofrectangular oblong strips. The dimensions thereof may vary greatly.Preferably the panels have a length exceeding 1 meter, and a widthexceeding 0.1 meter, for example the panels can be about 1.3 meter longand about 0.15 meter wide. According to a special preferred embodimentthe length of the panels exceeds 2 meter, with the width beingpreferably about 0.2 meter or more. The decorative pattern of suchpanels is preferably free form repetitions.

Core Layers

The core layer is preferably made of wood-based materials, such asparticle board, MDF or HDF (Medium Density Fibreboard or High DensityFibreboard), Oriented Strand Board (OSB) or the like. Also, use can bemade of boards of synthetic material or boards hardened by means ofwater, such as cement boards. In a particularly preferred embodiment,the core layer is a MDF or HDF board.

The core layer may also be assembled at least from a plurality of papersheets, or other carrier sheets, impregnated with a thermosetting resinas disclosed by WO 2013/050910 (UNILIN). Preferred paper sheets includeso-called Kraft paper obtained by a chemical pulping process also knownas the Kraft process, for example as described in U.S. Pat. No.4,952,277 (BET PAPERCHEM).

In another preferred embodiment, the core layer is a board materialcomposed substantially of wood fibres which are bonded by means of apoly-condensation glue, wherein the poly-condensation glue forms 5 to 20percent by weight of the board material and the wood fibres are obtainedfor at least 40 percent by weight from recycled wood. Suitable examplesare disclosed by EP2374588 (UNILIN).

Instead of a wood based core layer, also a synthetic core layer may beused, such as those disclosed by US2013062006 (FLOORING IND). In apreferred embodiment, the core layer comprises a foamed syntheticmaterial, such as foamed polyethylene or foamed polyvinyl chloride.

Other preferred core layers and their manufacturing are disclosed byUS2011311806 (UNILIN) and U.S. Pat. No. 6,773,799 (DECORATIVE SURFACES).

The thickness of the core layer is preferably between 2 and 12 mm, morepreferably between 5 and 10 mm.

Tongue-and-Groove Profile

After cutting a nested decorative workpieces in a set of separatedecorative workpieces, the side edge of a decorative workpiece of theset of separate decorative workpiece may be milled to produce a tongueor a groove profile, to make it possible to interconnect decorativeworkpieces, also click decorative workpieces, such as click laminates.The advantage thereof is an easy assembly requiring no glue. The shapeof the tongue and groove profile (FIG. 11) necessary for obtaining agood mechanical join is well-known in the art of laminate flooring, asalso exemplified in EP 2280130 A (FLOORING IND), WO 2004/053258(FLOORING IND), US 2008010937 (VALINGE) and U.S. Pat. No. 6,418,683(PERSTORP FLOORING).

Other Preferred Embodiments

Another preferred embodiment is a deco store front comprised in themanufacturing of decorative workpieces.

Or another preferred embodiment is a deco digital workflow comprised inthe manufacturing of decorative workpieces. The deco digital workflow isa system to manage the printing of decorative patterns by one or moredigital print devices in a method of manufacturing deco workpieces, thepreferred embodiment may comprise deco digital workflow system, forexample for determining decorative patterns, nesting decorativepatterns, digital printing nested decorative patterns on a decorationlayer and/or digital cutting nested decorative workpiece with printednested decorative patterns to separated decorative workpieces. To handlethe mixture of decorative patterns, nested decorative patterns a decodigital workflow system is important and advantageous, for example toknow from each nested decorative workpiece the correct nested decorativepatterns. This may be monitored by reading marks on the nesteddecorative workpiece wherein the readings are feed back to the decodigital workflow system.

The deco digital workflow system comprises preferably a managementinformation system (MIS) to provide information that the manufacturingof decorative workpieces require to manage themselves efficiently andeffectively and to analyze and to facilitate strategic and operationalactivities.

In a preferred embodiment a part of a decorative pattern is digitalprinted on a package wherein a decorative workpiece, whether or not withother decorative workpieces, is wrapped in the package and wherein thedecorative workpiece carries the decorative pattern. Prior the wrappingof the decorative workpieces the decorative workpieces may be collected.The collected decorative workpieces are preferably cut out of a nesteddecorative workpiece. The digital printing of the package is preferablymanaged by a deco digital workflow system.

The deco digital workflow system may manage the forming of relief on adecorative workpiece or a nested decorative workpiece by digital reliefapparatus.

A deco storefront may be comprised in the deco digital workflow system.A deco storefront is a cloud-based web-to-print solution to enabledecorative workpiece service providers or decorative workpiece buyers tocreate and manage online stores for manufacturing of decorativeworkpieces which is called a deco storefront.

Preferably a deco storefront is marketed as a hosted cloud service sothere is no high initial investment needed in servers, software,databases or expensive symmetrical internet connections. This reducesthe cost of deploying stores and improves their time-to-market.

The deco storefront may have an easy manageable store centre which isthe central hub from which stores are set up and orders are tracked. Itsdashboard preferably provides instant feedback about incoming orders andthe status of orders that are in progress.

The deco storefront preferably comprises an online editor whereindecorative workpiece service providers or editors may design or editdecorative patterns or add decorative images. This gives the ability tothe decorative workpiece service providers an innovative way of creatingpersonalized decorative workpieces.

The integration of the deco storefront in a deco digital workflow systemmay increase the efficiency by saving time in for example theautomatically downloading and processing orders of decorativeworkpieces.

Another preferred embodiment is a method wherein a part of a decorativepattern is digital printed on a package wherein a decorative workpiece,whether or not with other decorative workpieces, is wrapped in thepackage and wherein the decorative workpiece carries the decorativepattern. Prior the wrapping of the decorative workpieces the decorativeworkpieces may be collected. The collected decorative workpieces arepreferably cut out of a nested decorative workpiece. The digitalprinting of the package is preferably managed by a deco digital workflowsystem.

REFERENCE SIGNS LIST

Table of Reference Signs 100 Nesting method 302 Flexible sheet 201Decorative pattern 303 Flexible sheet 202 Decorative pattern 150 Nestingqueue 203 Decorative pattern 801 Bleed area 204 Decorative pattern 1Decoration layer 205 Decorative pattern 7 Decorative panel 206Decorative pattern 27-28 Long side 207 Decorative pattern 29-30 Shortside 208 Decorative pattern R1 Direction 209 Decorative pattern R2Direction 800 Decorative pattern 32 Tongue 301 Flexible web 33 Groove 5Decorative pattern 24 Locking means 11 Paper manufacturer 19 Cutting tosize 12 Paper roll 20 Floor laminate manufacturer 13 Decor printer 21Floor laminate 14 Gravure printing 4 Cross section 15 Inkjet printing 31Coupling means 16 Decor paper roll 9 Top layer 17 Warehouse 25Protective layer 18 Impregnation 810 Groove distance 805 Bleed distance807 Bleed distance 811 Tongue distance

1-15. (canceled)
 16. A method of manufacturing decorative workpieces, the method comprising the steps of: arranging a set of decorative patterns into a set of nested decorative patterns; and digitally printing the set of nested decorative patterns on a decoration layer; wherein the step of arranging the set of decorative patterns into the set of nested decorative patterns includes performing one of rectangular nesting and true shape nesting.
 17. The method of manufacturing decorative workpieces according to claim 16, wherein a relief of the set of decorative patterns correctly matches the set of nested decorative patterns.
 18. The method of manufacturing decorative workpieces according to claim 16, wherein the set of nested decorative patterns is digitally printed on the decoration layer in a quality zone of a digital print device and/or in a quality zone of a cutting plotter.
 19. The method of manufacturing decorative workpieces according to claim 16, wherein the step of arranging the set of decorative patterns into the set of nested decorative patterns includes performing a nesting-on-the-fly method, and the set of nested decorative patterns are digitally printed by a single pass inkjet printer.
 20. The method of manufacturing decorative workpieces according to claim 16, wherein, prior to the step of arranging the set of decorative patterns, performing the steps of: performing an image analysis on a content of a decorative image; and selecting a region-of-interest in the decorative image, as a decorative pattern in the set of decorative patterns, based on the image analysis.
 21. The method of manufacturing decorative workpieces according to claim 20, wherein the decorative image represents a wood pattern; and the image analysis is selected from counting an amount of knots, measuring a size of knots, measuring a distance of a knot and an edge of a region-of-interest in the decorative image, and measuring a density of wood grain lines.
 22. The method of manufacturing decorative workpieces according to claim 16, wherein, prior to the step of arranging the set of decorative patterns, performing the step of: adding a connect area and/or a bleed area to a decorative pattern in the set of decorative patterns.
 23. The method of manufacturing decorative workpieces according to claim 22, further comprising the step of: digitally printing a mark in the connect area and/or the bleed area; wherein the mark is selected from cut marks, saw marks, alignment marks, control marks, information codes of the decorative pattern, information codes of print parameters of the decorative pattern, information text of a first decorative pattern, and information text of print parameters of the decorative pattern.
 24. The method of manufacturing decorative workpieces according to claim 23, wherein the bleed area is filled with image content of the decorative pattern.
 25. The method of manufacturing decorative workpieces according to claim 16, wherein the nesting is contained in a deco digital workflow system to reduce a total waste of the manufactured decorative workpieces, and the deco digital workflow system includes a management information system.
 26. An inkjet printed decoration layer comprising: nested decorative patterns.
 27. An inkjet printed decoration layer according to claim 26, wherein the nested decorative patterns include true-shape nested decorative patterns.
 28. A decorative workpiece comprising: the inkjet printed decoration layer according to claim 26 heat pressed with a core layer and a protective layer; wherein the decorative workpiece is selected from the group consisting of flooring, kitchen, furniture, and wall panels.
 29. The decorative workpiece according to the claim 28, wherein a package wrapped around the decorative workpiece includes a digitally printed portion of the decorative pattern.
 30. A method of manufacturing decorative workpieces comprising performing a nesting method to reduce waste in the manufacturing of the decorative workpieces. 